In response to the needs for lighter, thinner and smaller products, the notebook computer manufacturers especially have to improve their designs continuously just to catch up with the trend. However, the quest for even thinner notebook computers should not take the elastic touching feeling of its press-keys as sacrifice just for the sake of achieving a thinner keyboard. Conventionally, a press-key is usually constructed with a scissors-type elastic structure, as shown in FIG. 1 and FIG. 2. The aforesaid press-key 10 is comprised of: a keycap 14, a substrate 13 and two supporting arms 11, 12 sandwiched between the keycap 13 and the substrate 14. In FIG. 1, the two supporting arms 11, 12 are pivotally coupled with each other at the middle thereof forming an X-shaped structure. It is noted that the aforesaid conventional press-key 10 is assembled by the procedures described as following: the first step is to inset the pivotal axes 112, 122 of the two supporting arms 11, 12 respectively into the joints 131, 132 formed on the substrate 13 so that the two supporting arms 11, 13 are connected with the substrate 13 and thus the press-key 10 is semi-finished; and then by connecting the keycap 14 to the tops of the two supporting arms 11, 12, the press-key 10 is completed.
As shown in FIG. 1, there are a coupling structure 141 with lateral engagement opening and another coupling structure 142 with vertical engagement opening that both are formed on the bottom of the keycap 14. Thus, when it comes to the assembling of the keycap 14, first the keycap 14 must be tilted by a specific angle for enabling the first pivotal axis 111 formed on the top of the supporting arm 11 to be inset into the lateral engagement opening of the coupling structure 141; and then the keycap 14 is pressed downwardly for engaging the vertical engagement opening coupling structure 142 with the second pivotal axis 121 formed on the top of another supporting arm 12, as shown in FIG. 2.
As the aforesaid conventional press-key 10 is so-structured, it must be assembled manually so that it is disadvantageous in that: not only its production efficiency as well as its yield are poor, but also the keycap is very easy to be damaged during the manual insetting the two engagement openings with the tops of their corresponding supporting. Moreover, as the two supporting arms 11, 12 are pivotally coupled with each other at the middle thereof forming an X-shaped structure, the keycap 14 must be elevated by a specific height that has no way to be reduced.